Taking pictures at a paranormal investigation you suddenly see something that catches your attention.You excitedly look over your pictures and see that you have gotten pictures of spirit Orbs.What you may not realize is that you more than likely have gotten pictures of reflections from your camera flash off of dust,dirt bugs or moisture in the air.
Dust: This is one of the most common orb anomalies which are mistaken for paranormal orbs.
Water: This can be from rain or even un-noticeable high humidity in the area.
Bugs: This is another really common issue. Many times especially outside, bugs will often appear as spot/orbs. With the new digital cameras they also appear a "rods" which is when the camera will capture the bug many times as it moves through the field of vision and is usually associated with video.
A paranormal orb,if you are ever lucky enough to catch one,will emit it's own light or power source and you won't need a light source to see it,or make it light up.